This renewal application is to support predoctoral and postdoctoral training in the study of the brain at the level of neural systems and behavior. The program is intended to produce new Ph.D.'s and postdoctoral scientists capable of establishing independent research in the field of neuroscience. The training program will be operated by the highly successful, interdisciplinary Neuroscience Graduate Program at Brown University. The 18 members of the training faculty are drawn from the Departments of Neuroscience (13), Psychology (3), Cognitive and Linguistic Sciences (1), and Applied Math (1). Their research is on the mechanisms of the brain which cause behavior, with a strong focus on use of combined methods at different levels of analysis to understand specific brain systems. Some faculty work at the cellular level to understand processes which specifically manifest themselves in the overall performance of the systems to which these cells belong, while others work at the level of neuronal populations to understand their connectivity or information-processing functions in relation to behavior. Several faculty use behavioral measures in conjunction with physiological experiments and modeling of neural systems, while others work with computational models, bringing behavioral experiments and modeling of neural systems, while others work with computational models, bringing behavioral or physiological data to bear on testing the validity of the model. The breadth of training in the program is enhanced by emphasizing the advantages of using a variety of different methods and the different perspectives these methods bring to research, rather than having individual laboratories separately study brain function using anatomical, physiological, behavioral, or quantitative methods in isolation. The program uses courses, supervised laboratory research, a strong colloquium series, seminars, journal clubs, and special social-scientific functions to train students in the practical, day-to-day conduct of research on brain function from a multi- disciplinary perspective. Funds are requested for 5 years, for 4 predoctoral trainees and 4 postdoctoral trainees.